Core/PacketIO: Fixed CMSG_MESSAGECHAT_ADDON_BATTLEGROUND

https://github.com/TrinityCore/TrinityCore/commit/6446a73cc11278aaf3cfd5c0f8d9456f8bb3352e
Battlegrounds: Better log message for unhandled area triggers in battlegrounds.

https://github.com/TrinityCore/TrinityCore/commit/2a89658e969e28caae7f3d11d722ffbdcd284d72